Bags or pouches of this type are used for receiving waste in generally liquid form, particularly waste of human origin such as urine or vomit. Such pouches are normally in their flattened form and are opened to receive the waste. On that occasion, the pouch is held in the vicinity of the free end of the collar to oblige the latter to adopt its substantially tubular configuration. Once the waste has been introduced, it suffices to release the free end of the collar so that it naturally resumes its flattened configuration, thus closing the opening.
Such pouches are currently made with thin sheets of paper or of plastics material, possibly transparent, endowed with the desired suppleness. For opening, the reinforcing element is deformed by the user, which obliges that part of the collar disposed around this element, to adopt the desired tubular configuration.
The transverse dimensions of the opening are chosen to suit the use which it is desired to make of the pouch. Generally, especially when the pouch is intended to receive urine or vomit, the opening must be able to be manipulated with one hand, with the result that its transverse dimensions are clearly smaller than the current transverse dimensions of the pouch. For example, when the pouch is used as urinal, its maximum width and that of the opening may vary respectively between 15 and 20 cm and between 4 and 10 cm, depending on whether the user is an adult or a child.
The presence of the reinforcing element makes it possible to open the opening of the upper end of the collar by bringing together the two longitudinal edges of this element which determine its maximum width in the flattened configuration. However, due to the suppleness of the material which constitutes the outer envelope of the pouch, there is a risk that only the collar is suitably opened, while the rest of the outer envelope remains flat, the sheets which constitute this envelope naturally tending to remain "stuck" to one another. Consequently, when the pouch is being used, there is a risk of reflux towards the outside for the product poured in the pouch.
It is an object of the present invention to overcome this drawback by proposing a pouch or bag for which the passage of the collar to the tubular configuration ensures spacing apart of the walls of the outer envelope not only in the region of this collar, but also at least in the region of the widened part near the collar.